1. Field of the Invention
This invention relates to a display apparatus and connecting cables used in the display apparatus for the electrical connection.
The present application claims priority from Japanese Application No. 2002-359588, the disclosure of which is incorporated herein by reference.
2. Description of the Related Art
Some display apparatuses have a flat display panel such as a plasma display panel (hereinafter referred to as “PDP”), a field emission display panel (hereinafter referred to as “FED”), an organic or inorganic EL display panel, or a liquid crystal display panel.
For example, the PDP is structured such that a pair of front and back substrates are placed in parallel opposite to each other with a discharge space in between, and the periphery of the discharge space is sealed.
More specifically, a reflection-type AC PDP has a plurality of row electrode pairs formed on the inner surface of the front substrate for creation of a surface discharge (display discharge), and a dielectric layer covering the row electrode pairs. Further, on the inner surface of the back substrate facing the front substrate, a plurality of column electrodes are arranged in a direction at right angles to the row electrode pairs for creation of a selection discharge between the column electrode and one row electrode in each row electrode pair, and a column electrode protective layer covers the column electrodes. Between the front substrate and the back substrate, a partition wall is formed for partitioning the discharge space into discharge cells, and phosphor layers of the three primary colors (i.e. red, green and blue colors) are respectively formed in all the discharge cells such that the red, green and blue cells are arranged in order.
FIG. 1 and FIG. 2 illustrate a conventional structure of electric connection between such a PDP and a driver board for driving the PDP in a display apparatus having the PDP.
FIG. 1 is a schematic plan view illustrating the relationship between the PDP and the drive circuit board. FIG. 2 is a sectional side view partially enlarged for illustration of the electric connection between the driver board and an electrode terminal extended from a row electrode of the PDP of the display apparatus.
In FIG. 1, one row electrode in each row electrode pair of the PDP 1 of the display apparatus is connected to a sustaining driver board 2A through an associated flexible cable C1. The other row electrode in each row electrode pair is connected to a scanning sustaining driver board 2B through an associated flexible cable C2.
Each of the column electrodes of the PDP 1 is connected to an addressing driver board 2C through an associated flexible cable C3.
FIG. 2 illustrates an electric connection between one row electrode in the row electrode pair and the sustaining driver board 2A through the flexible cable C1 as an example of the electric connection between the PDP 1 and each of the driver boards.
The following describes the electric connection between one row electrode in the row electrode pair of the PDP 1 and the sustaining driver board 2A by means of the flexible cable C1 on the basis of the structure in FIG. 2. However, the structure of the electric connection between the other row electrode in the row electrode pair and the scanning sustaining driver board 2B by means of the flexible cable C2 and the structure of the electric connection between the column electrode and the addressing driver board 2C by means of the flexible cable C3 are substantially the same as the structure illustrated in FIG. 2.
In FIG. 2, the electrode terminal 1A extended from one row electrode in the row electrode pair of the PDP 1 is coated with an anisotropic conductive adhesive a of a thermosetting property. One end C1a of the flexible cable C1 is placed in a predetermined position to overlap the electrode terminal 1A and then thermo-compressively bonded to the electrode terminal 1A for the electric connection.
As in the above case, the electrode terminal 2Aa of the sustaining driver board 2A is coated with an anisotropic conductive adhesive b of a thermosetting property. The other end C1b of the flexible cable C1 is placed in a predetermined position to overlap the electrode terminal 2Aa and then thermo-compressively bonded to the electrode terminal 2Aa for the electric connection.
Approximately the same structure as the aforementioned structure is used for the electric connection between any other flat display panel, such as an FED, an organic or inorganic EL display panel or a liquid crystal panel, and its driver board.
Such the foregoing conventional display apparatus is showed in JP Pat. Publication No. 2000-150033.
As described earlier, the thermo-compression bonding technique using an anisotropic conductive adhesive of a thermosetting property is used for the electric connection between the electrode terminal of the flat display panel and one end of the flexible cable and the electric connection between the other end of the flexible cable and the electrode terminal of the driver. This is because if the electric connection is implemented by using a connector, any foreign substance such as dust and the like may adhere to the inside of the connector during the manufacturing stage in a factory and may cause contact failure. Further the use of the thermo-compression bonding technique using the anisotropic conductive adhesive makes it possible to reduce the production costs of the display apparatus.
However, the conventional display apparatus structured as described above has some problems. For cases where a driver board connected to the flat display panel is faulty and needs replacement, the electric connection between the flexible cable and the driver board is made by means of the thermo-compression bonding technique using an anisotropic conductive adhesive, and the use of thermo-compression bonding technique makes the drive-board replacement difficult in the location of the display apparatus, such as a household. Therefore the display apparatus must be carried to a workshop for replacement work using specially designed equipment, which then requires enormous effort and greatly increases repair costs.